"A copy of this account already exists in Contacts" (but it doesn't)

Question

Running an early 2013 MacBook Pro Retina, on the latest version of Yosemite (10.10.3). I can't enable Contacts for my Exchange account in Internet Accounts. I already have Mail and Calendar selected, but when I select the checkbox for Contacts, it deselects itself a moment later (i.e. the checkmark disappears on its own). I checked out Console to try to get to the bottom of the error, and it tells me that "A copy of this account already exists in Contacts." It doesn't - this is my only Exchange account in Contacts.
I've tried deleting and re-adding the account, rebooting, fixing permissions, and checking for disk errors. No luck. Any ideas? Thank you.

Answer 1

I think I fixed this. The first time I deleted the account and re-added it, I chose the option to only delete it from my MacBook. I just tried again, and chose the option (in a dialog box that pops up) to delete the account on all devices. After that, I re-added the account, and Contacts now works.